Still can't rule out the possibility that he's an American jihadi convert.
By that logic, you can't rule out the possibility that he's pissed off about Ruby Ridge, either.
Did you read the article? He's a psychopath. The girl killed in the AM was not his g/f. Her ex was in some interrogaiton room at the time of the 2nd shooting. The guy was a loner, no friends noted, his English profs turned hin in to the U counseling service, because of his disturbed writing, and the counseling service determined that he was bizarre. He committed arson in the dorm recently and was otherwise noted as committing hostile acts recently.
Islam has nothing to do with it, other than picking up coincidental pieces of lunacy. He could very well have picked up Chistian characters as elements of his psychosis.